hofmann



(No Model.) 4 Sheets-Sheet I. A. W. HOFMANN. METHOD OF AND MEANS FORORNAMENTING WATCH CASE BAGKS AND GOVERS AND OTHER LIKE ARTICLES;

Patented Sept. 2, 1890.

INVENTEIR Z2? NEEEES:

(No Model.)' 4 Sheets-Sheet 3. A. W. MANN.

METHOD OF AND MEANS FOR MEN I G WATG SB BACKS AND COVERS AND OTHER LARTIGL No. 435,836. m/Patented Sept. 2, 1890.

- gg magggg ggagflmiggggg gmguum m jmw (No Model-.) 4 Sheen -Sheet 4. A.W. HOFMANN.

METHOD OF ANDMEANS FOR ORNAMENTING WATCH CASE BACKS AND oovms AND OTHERLIKE ARTICLES.

No. 435,836. tented Sept. 2, 1890.

WIT/\IEEEES/ Pk UNITED STATES PATENjr OFFICE.

ADOLPH V. HOFMANN, OF BROOKLYN, ASSIGNOR TO ROBBINS (it APPLETON,

OF NEW YORK, N. Y.

METHOD OF AND MEANS FOR ORNAMENTING WATCH-CASE BACKS AND COVERS ANDOTHER LIKE ARTICLES.

' SPECIFICATION forming part of Letters Patent NO- 435,836, datedSeptember 2, 1890.

Application filed November 9, 1889. Serial No- 329,'7Z6. (N0 model.)

To aZZ whom it may concern:

Be it known that I, ADoLPH W. HOFMANN, of Brooklyn, in the county ofKings and State of New York, have invented certain new and usefulImprovements in Methods of and Means for Ornamenting lVatclrGa-se Backsand Covers and other Like Articles, of which the following is aspecification.

This invention relates to the ornamentation of watch-case backs orcovers by pressing an engraved roll against the work or article to beornamented and causing the roll to form a circular or annular path ofornamentation extending around the work either by rotating the work onits own axial center and holding the roll at a given point in rollingcontact with the work, or by holding the work stationary and revolvingthe roll about it, the roll being rotated by its contact with the workwhile revolving about it.

In two applications for Letters Patent filed by me December 31,1887,Serial Nos. 259,495 and 259,496, I have described a method whichinvolves rotating the work and holding the roll at a given point, theroll having no revolving motion about the work, and in anotherapplication filed August at, 1888, Serial No. 281,921, I have shownmeans for revolving the roll about the work, the latter being heldstationary, the roll being caused in each case to ornament the work in apath that is concentric with the center thereof, said path being widenedby a swinging movement of the roll until the entire surface isornament-ed. The motion which causes the roll to form said circular pathof ornamentation is described in said applications, as alternating-thatis, progressing first in one direction and then in the oppositedirection-the movement in each direction being sufficient to cause theroll to form a continuous circular path of ornamentation around thework. The object of the alternating rotary motion is to enable the rollto make sufficiently deep indentations in the work by being held at thesame point until its action on the same portion of the path ofornamentation has been repeated several times, the alternating motionenabling the relief-lines of the roll to remain in engagement with theindentations made thereby in the work, so that ateach pass or movementof the work the roll deepens the indentations made during the precedingpass until the ornamentation is suifieiently deep. If the rotary motionof the work were continuous or always in the same direction, there wouldbe much liability of failure of the relief-lines of the roll to coincidewith the initial indentations made in the work after the first completerotation, and in the event of such failure the ornamentation would bedestroyed.

In my former applications above referred to the ornamenting-roll isshown as adapted for the ornamentation of the crowning peripheries ofwatch-case centers, the roll being cylindrical and of uniform diameterfrom end to end. The present invention relates partieularly to theornamentation of surfaces such as the sides of watch case backs in whichthe surface to be ornamented or a part thereof extends substantially atright angles with the axis or center of the motion that causes the rollto make the circular path of ornamentation, so that a cylindrical rollof uniform diameter, such as is shown in my former applications cannotbe used, because such a roll when held against the side of a case-backwith its axis substantially at right angles with the axis of rotation ofsaid back would slip on parts of the surface of the work and thus mar ordestroy the ornamentation.

My invention therefore consists, first, in the employment of a conicalor tapering roll or preferably formed as a cone frustu m, the apex ofwhich if continued would be at the center of the surface to beornamented when one side of the roll is in operative relation to saidsurface, so that the roll will indent the surface and form the path ofornamentation thereon without slipping upon said surface.

The metal of watch-case backs is usually so thin that its area isextended by the pressure of the conical ornamenting-roll against it; andmy invention has for its further object to prevent the displacement ofthe metal caused by its extension or the enlargementof its area fromdistorting the back or disk-shaped piece of work while it is beingornamented. The invention therefore consists, also, in clamping thecenter of the work firmly to the chuck, leaving its marginal portionfree to expand or creep outwardly under the pressure of the IOC conicalornamentiug-roll and then applying said roll first to the portion of thework immediately adjoining the clamped center and moving the roll tocarry its place of contact with the work outwardly as the operationprogresses, the work being given at the same time an alternating rotarymotion so that the path of ornamentation widens outwardlyfrom thecenter, and the metal displaced by the ornamenting action creepsoutwardly to the free margin of the work, the extension of the area ofthe work being thus permitted Without causing the work to bulge orbuckle, as it would do if rigidly confined at its margin.

The invention also consists in the improved means for clamping thecentral portion of the work and for supporting the ornamentingroll, allof which I will now proceed to describe.

In the accompanying drawings, forming a part of this specification,Figure 1 represents a top plan view of a portion of the lathe spindle orchuck which supports and rotates the work, together with thework-clamping devices, the ornamenting-roll, and the means forsupporting and moving said roll. Fig. 2 represents a side elevation ofthe parts shown in Fig. 1. Fig. 3 represents a section on line 3 3,Fig. 1. Fig. 4 represents an enlarged section on line 4 4., Fig. 1. Fig.5 represents a side elevation of the mechanism shown in Figs. 1 and 2with mechanism for reversely rotating the work-support.

The same letters of reference represent the same parts in all thefigures.

In the drawings, a represents a chuck or .spindle, which is formed tosupport the inner or concave side of a watch-case back b, and isattached to a shaft 0, which is journaled in bearings d, supported bythe bed orsupporting-frame 6. Means are provided for giving said spindlean alternating rotary motion, such means being, for example, a pinion f,affixed to the shaft 0, and a rack g, which is suitably connected to aneccentric wrist-pin h on a driving-shaft t', as shown in Fig. 2, and inmy prior application above referred to. The chuck is simply a solidsupport for the inner surface of the case-back b or other work to beornamented, and is not. constructed to grasp and rigidly hold said backunaided. The back is confined upon the chuck by means of arigidly-supported adjustable arm j, having aprojection or pivot j, and aclamping plate or button k,havinga step or socket is, which receivessaid pivot, and is held thereby against the outer surface of the back 1)at the center of the latter, the pivot j being on the axial line of thechuck, so that the clamping plate or button is is free to rotate withthe chuck and back. The arm j is attached by a set-screw Z to a post mon aslide n. Said slide is adjustable in a direction parallel with theaxis of rotation of the chuck, so that the arm j can be moved toward andaway from the chuck to clamp and release the back. The slide is fittedto move between dovetail guides o' 0 in a supportingbase 0, and isprovided with a screw 19, which is engaged with a nut q, formed on saidbase, Fig. 3, so that the rotation of the screw moves the slide at andthe arm j and adjusts the latter, as above described. The arm j iscapable of exerting sufficient pressure on the clamping plate or buttonit to enable the latter to clamp the central portion of the backb sofirmly against the chuck a as to keep the back operatively engaged withthe chuck, so that the back will necessarily rotate withthe chuck. Theback is, however, thus clamped only at its central portion, its marginalportion being free to expand or be extended by the action of theornamenting-roll, as hereinafter described.

The supporting-base o is attached by screws u u to a slide c, which isfitted to move at right angles with the axis of the chuck in guides on abed-piece w, which is securely affixed in any suitable way to thelathe-bed e, and is adjustable by a screw 00, journaled in the slide 4:,and suitably engaged with the bed-piece w, so that byits rotation itwill adjust the slideoand the parts carried thereby.

To the slide '0 is rigidly affixed a circular socket A, in which isfitted to rotate freely a horizontal circular plate B. To said rotaryplate is attached an arm O,having a horizontal socket 0', through whichpasses a longitudinally-movable stud D.

E represents the ornamenting-roll, the periphery of which is tapering,and is here shown as a frustum of a cone, engraved with the design to beimparted to the back I), the proportions of the roll being such thatwhen it is held in operative relation to the work, as shown in Fig. 1,the apex of the cone if continued would be at the center of rotation ofthe work. Said roll is journaled in ears F F at one end of the stud D,and is adapted to be pressed by said stud against the back I). The arm 0and stud D are adapted to move horizontally in the are of a circle, theplate B, to which said arm is attached, permitting such movement, sothat the roll E can be first held in the position shown in Fig. l withits periphery in contact with the back at a point in close proximity tothe clamping plate or button 70, and can then be moved to cause itsperiphery to act 011 the curved marginal portion of the back I).

In practice with the apparatus organized as here shown and described,after the back I) has been clamped to the chuck and the alternatingrotary motion has been imparted to the chuck, the operator holding theroll E in the position shown in Fig. 1 by means of the handle I,attached to the stud D, presses the roll against the back, and thuscauses the re lief-lines of the roll to sink into the back and form anannular path of ornamentation close to the clamping plate or button is,the roll being held in one position until the ornamentation issufficiently deep. The position of the roll is gradually changed byswinging the arm C in the direction indicated by the arrow in F g. 1until the path of ornamentation is widened to the margin of the case.The dis placement of metal by the compressing action of theornamenting-roll is entirely outward, or from the center toward themargin, and as the margin is unconfined there can be no distortion ofthe back, which would tend to separate it from the chuck, the back beingkept 1n close contact with the chuck and only changed by the slightenlargementof the circle of its margin.

I do not limit myself to the employment of the conical or taperingornamenting-roll in connection with means for rotating the work, as theroll may be given a revolving motion about the work by any suitablemeans. Neither do I limit myself to the use of said roll in connectionwith means for centrally clamping the work, as I may use it inconnection with any other suitable work holding or clamping devices. 1

It is obvious that the advantages resulting from the employment of aconical roll as the means of forming a circular path of ornamentation ona surface which is substantially at right angles with the axis or centerof the motion which causes the roll to make said pathviz., the freedomfrom liability of the roll to slip on and mar he surface beingornamentedwould be the same if the said motion were continuous insteadof alternating. Hence I do not limit myself to the use of a conical rollin connection with an alternating movement of the work or of the roll.Although I have not here shown means for imparting an alternating motionto the roll to carry the same back and forth about the work, yet it isobvious that the mechanism shown in my above-named application, No.281,921, filed August 45, 1888, can be readily adapted to carry aconical roll.

I claim- 1. The combination, with a support for a watch-case back orother like article to be ornamented, of means for giving an alternatingreciprocating motion to said article to be ornamented, a conical ortapering ornamentingroll, and means for pressing said conical rollagainst the article to be ornamented, and for imparting rocking motionto said roll while it is held pressed in contact with said article,substantially as described.

2. The improved method, hercinbefore described,of ornamenting watch-casebacks and other articles of like form, the same consisting in presentinga conical or tapering ornamenting-roll to said articles, causing theroll to form a circular path of ornamentation by an alternating motioneither of the roll or of the article being ornamented, and rocking theroll while in contact with said article to widen the path ofornamentation, as set forth.

3. The improved method, hereinbefore described, of ornamentingwatch-case backs and like disk-shaped articles, the same consisting inclamping the said article at its center only to a supporting-chuck,leaving the marginal portion uncon fined, rotating the chuck and theback clamped thereon, and pressing an ornamenting-roll against the back,beginning at a point in close proximity to the center of the back andmoving the roll to carry its point of contact with the back outwardlyfrom the center to or toward the margin, as set forth.

4. The combination of the chuck or worksupport, a clamping plate orbutton formed to bear upon the outer surface of a piece of work on saidchuck, a pivot engaged with said plate, and means for exertingpressurethrough said pivot on said clamping-plate, as set forth.

5. The combination of the chuck or worksupport, a clamping plate orbutton formed to bear on the outer surface of a piece of work 011 saidsupport, a movable arm having a pivot engaged with said plate, and meansfor adjusting said arm and holding it at any position to which it may beadjusted, as set forth.

6. The combination of the chuck or worksupport, the clamping plate orbutton, the arm j, having a pivot or projection engaged with said plate,the slide 91, having a post supporting said arm, and the ad justing-screw engaged with said slide and with the support on which the latterbears, as set forth.

7. The combination of the chuck or worksupport, means for securing awatch-case back or other like article thereto, the slide r, adj ustableat right angles to the axis of rotation of the chuck, a socketed armaffixed to a supporting plate or base which is fitted to rotate in asocket on said slide, a stud supported by and movable in said arm, andan ornamenting-roll journaled in cars on said stud, as set forth.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, this 7th day of November, A. D.1889.

AD OLPH \V. HOFMANN.

Witnesses:

J. E. SEARING, C. II. WALKER.

ICC

